1. Technical Field
The present invention relates to monitoring cardiac function of a patient during a magnetic resonance imaging (MRI) procedure, and more particularly, a method and system for monitoring cardiac function of a patient during an MRI procedure without an electrocardiogram (ECG).
2. Discussion of the Related Art
Catheterization based methods like angioplasty, valve replacement, stent replacement, and ablation for atrial fibrillation are widely performed under X-ray monitoring and guidance. These methods, however, involve the use of ionizing radiation, which is a risk for the patient and the medical personnel conducting the procedure. Magnetic resonance imaging (MRI) would be a preferable alternative to X-ray, not only because of its lack of ionizing radiation, but also because it provides superior soft tissue contrast in images. One of the major challenges of interventional MRI is patient safety during the procedure. For example, standard monitoring devices, such as an electrocardiogram (ECG), are disturbed by the magnetic field environment and cannot be interpreted during MRI. See e.g., [Fischer, S. E., et al. (1999), “Novel real-time R-wave detection algorithm based on the vectorcardiogram for accurate gated magnetic resonance acquisitions”, Magn Reson Med. Vol. 42(2), pp. 361-370]. Yet, real-time updates on heart function and structure during an MRI procedure are critical for interventional cardiovascular MRI, in particular, as well as for diagnostic dobutamine stress testing with MRI.
Accordingly, there is a need for a technique that enables real-time updates on heart function during an MRI procedure.